why older people cannot taste as well?
the receptors get downregulated
why some people taste very bitter or tasteless?
- gene inherited
which nerve innervates for the anterior 2/3 of the tongue?
chorda tympani facial nerve CN VII
which nerve innervates for the posterior 1/3 of the tongue?
glossopharyngeal nerve lingual branch
which nerve innervates the epiglottis?
vagus nerve CN X
what is the function of basal cells?
dividing and replacing to form new taste cells
how are different smell caused?
different chemicals bind to different receptors
what is the function of receptor neurone?
receives information from the receptor
what is the funciton of sustentacular cell?
structural support
what is the function of basal cell?
deepest layer of stratified epithelium
what is the function of secretary cells of bowman’s glands?
secrete gel forming mucin
what is the function fo olfactory ensheating cell?
- ensheath the non-myelinated axons of olfactory
- assist in axonal regeneration
describe taste transduction?
- G protein triggered
- ligand gated system
- metabtrophic response
- trigger release of calcium from stores
- calcium will trigger release of neurotransmitters in the nerve cells and induce transfuction
describe smell transduction?
- odorant binds to receptor
- activates G-protein (Golf)
- alpha subunit activated adenylyl cyclase
- generates cAMP
- open cation channel
- depolarisation and calcium release
- calcium open chloride channels
what is the function of tufted cell?
- projection neurons
- send signals from glomeruli deeper into the brain
how does tufted cell make actual signals sharpened?
through lateral inhibition
where does mitral cells receive information from?
axons of olfactory receptor neurons
where does mitral cell receive excitatory input from?
- olfactory sensory neurons
- external tufted cells
where does mitral cell receive inhibitory input from?
- granule cells
- periglomerular cells
what does periglomerular cells do?
lateral inhibition in the olfactory system
what does granular cells do?
helps with lateral inhibition
where does the sensory pathway for taste go to?
Nucleus of the solitary tract then to ventral posterior nucleus
does the olfactory information sent to both side of the brain? if yes where do they cross?
yes, cross at the anterior commissure
what is the importance of the anterior perforated substance?
- blood vessels perforate through to provide blood supply to the central part of the brain
